Research Article

Two New Reference Materials Based on Tobacco Leaves: Certification for over a Dozen of Toxic and Essential Elements

Figure 7

Comparison of the finally calculated overall mean (from the alternative database) for Zn and Cr in INCT-OBTL-5 and the means obtained for particular analytical techniques, together with the respective confidence intervals.
216380.fig.007a
(a)
216380.fig.007b
(b)